Dimmension
by oblivion-starr
Summary: Alien Force. In an alien battle, Ben falls victim to a strange transportation device. Upon waking up he finds himself in a parallel dimension. Can he convince Gwen, Kevin, and Grandpa Max to help him return to where he belongs? Some B/J and G/K. R&R!
1. Chapter 1

(I do not own the rights to Ben Ten Alien Force nor its characters, etc. I apologize in advance if this story is a little OOC.)

It was just one of those days where you just didn't want to get out of bed and face the day ahead of you. The sun was shining into a small bedroom, its rays trying to yank the fifteen year old boy still snoozing away from dreamland and into reality. Just what had he done to deserve that? It just didn't seem fair. Finally when the light was just too intense to ignore any longer, green eyes flickered upon and the brown haired boy sat up, a yawn passed through his lips as he stretched his arms up above his head.

A hand went to his head as though he had given himself a headache and he laid himself back down. It wasn't as though Ben Tennyson was a lazy teenager who liked to sleep in late. No, he had been up late the night before. His mind swam for a moment as he tried to remember just what had happened before he had gone to bed. It was strange, but he couldn't even recall having gone to sleep in his home. The last thing that he had remembered doing…

Launching himself out of bed, the memory coming back like a ton of bricks all of a sudden, Ben darted across his room and grabbed the familiar green jacket that he always wore. Having still been dressed in his blue jeans and black t-shirt, all he had to do to get ready besides that was slip on his tennis shoes. Once that was done he flung his door upon and headed for the stairs at a fast pace his cell phone already being pulled out of his right pant pocket. Punching in the familiar number, Ben held it to his ear as he listened to the slow sound of it ringing on his end.

There was a click and a voice on the other end, a feminine yet disgruntled one, asked 'hello?' tiredly into his ear. A smile formed on Ben's face as soon as the connection was made and he seemed to relax. "Hey Gwen, it's me. I was just calling to find out what happened last night? I woke up in my bedroom this morning but I don't remember how I got there." He scratched his head slightly with his hand that wasn't holding the phone. Sure enough, all he could remember was that Gwen, Kevin, and he had been fighting some aliens the night before. Then there had been a flash of blinding light and he had felt himself pass out. After that there was nothing until he had woken up in his own bedroom.

"How the heck would I know?" Gwen questioned followed by the sound of her yawning. "I wasn't with you last night. We hardly ever hang out. We're cousins but it's not like I know you're every move, jeez. Call sometime when it's not seven in the morning next time, okay Ben? Bye." There was an audible click as she hung up on him that caused the teenager a look of surprise, his mouth practically falling open. It was evident that he hadn't expected such a cold response.

"That was… bizarre." Lowering his phone from his ear, Ben allowed himself a moment of thought. It made no sense at all what his cousin had just told him. Lately they had been hanging out constantly. There were alien menaces to be dealt with, after all, and Gwen, Kevin, and he were the ones to help stop that; Ben with his Omnitrix, Gwen with her "magic," and Kevin with his absorption powers. Almost every night now the three of them went out to look into strange occurrences in the surrounding areas. Even Ben's parents knew about their special abilities. So just what was going on here?

"Okay, I don't know what's going on with Gwen, but obviously something is wrong and I'm going to find out what," Ben said with determination on his youthful face as he ran out of the house, barely remembering to close the front door behind him. Raising his right hand, the other came to his wrist. Fingers gently moved the device, which resembled a normal watch, as figures took form as green holographic images above it. He switched the figures a few times before a look of satisfaction appeared on his face. With one quick motion, he slammed down the round top.

What happened next would have been startling to anyone else but Ben calmly spread his arms out, green light forming around him, as the cellular structure of his body literally changed. Flaps of skin came out from his arms, forming into wings, then a tail after that. The bones of his hands literally stretched themselves until they formed into something like claws. Soon the rest of him changed as well, his face included.

"Jet Ray!" he said in a voice that was more nasally than his normal one before he pushed off from the ground and rose into the air. Gliding literally like a jet, he flapped his arms just once before taking off like a bullet in the direction he knew Gwen's house to be in. His thoughts screamed for him to go faster in case his cousin was in some sort of danger. Why else would she have said those things?

Soon enough, he spotted the small square that was her house even from the incredible height he was flying at. Diving downward, he only pulled up when he was mere feet away from the ground. As soon as his feet touched down, there was another burst of bubbling green light and he began to run as himself toward the front door. There were no signs of a struggle anywhere nearby, he observed with some relief. Still, that didn't mean that she wasn't in some sort of trouble. The thought that he should call Kevin caused him to flip open his green phone again. Punching in the numbers even as he ran, Ben then waited for it to ring, only to hear a disconnected signal.

"What's going on here?" he questioned in perplexity before he stuffed the phone back into his pocket and banged on the front door. For a moment he had forgotten that he could have just crashed into the house using one of his ten alien forms. Realizing that now when he didn't get an immediate answer, he was just about to use Mage Chill when the door was pulled inward and, since he had been leaning on it, stumbled inside with a cry of surprise at first. Regaining his balance, Ben's green eyes shot upward to look directly into his cousins.

"Ben, what are you doing here? I just got finished telling you not to call so early in the morning when you come knocking at my door! What in the world could be this urgent that you have to be this… inconsiderate?" Gwen questioned fiercely, her hands on her hips and eyes narrowed considerably at him. Catching his breath finally, the Omnitrix wielder straightened himself up and was about to speak when his cousin interrupted him. "Wait, how did you get here that fast anyway? Were you at home when you first called?"

"It's not like I always have to walk you know," Ben responded with a raised eyebrow, wondering why that was so shocking to his cousin when she knew that he had two aliens that both had the ability to fly. "I just used Jet Ray to fly here. I was worried when you acted so weird on the phone earlier that something was wrong. Plus I couldn't get a hold of Kevin…"

"Jet Ray; what are you talking about Ben?" Gwen questioned as though she was just now hearing the name. Her cousin stared at her with a mixture of shock and horror. "Who's Kevin anyway?" It just seemed to be getting progressively worse. The first thought that occurred to Ben was that his cousin was suffering from some form of alien mind control. No, that didn't make sense. Besides, that kind of stuff only happened in the movies as far as he knew. Although you could never be too careful when you actually knew that aliens did, in fact, exist.

"Gwen, are you feeling alright?" Ben questioned with a concerned look. "Jet Ray is one of the guys I can turn into. Did you just not get enough sleep last night or something?" Again, this earned him a strange glance from the long haired red head. "Gwen, I'm talking about the Omnitrix. It lets me transform into any of ten aliens?" This only increased the odd way that he was being looked at. In fact, Gwen was starting to get visibly angered again. He was reminded considerably of when they were younger and he had just done something like calling her "booger for brains" or the like. It had been five years since he had acted like that, however, and Gwen had considerably chilled herself since then. So, what was with the sudden change?

"You are so immature Ben!" she shouted, throwing her arms up into the air in frustration. "I ask you a simple question and actually try to be a little understandable and you just throw it back in my face and make up ridiculous stories. I'm tired of it Ben. You can go play "make believe" somewhere else, alright?" Opening the front door wide, she gestured with one long arm out the door. She was actually kicking him out of the house!

"Wait a minute Gwen," Ben said calmly, raising his hands and shaking his head. "I really don't know what's going on here but I'm not making up anything. Just look." Ben held up the wrist with the Omnitrix on it to show her. "This is proof right here that I'm telling the truth." Sure enough, it was proof. The only thing was that his cousin didn't seem to know about the device at all. Or if she hadn't just plain lost her memory, was doing a very terrible April Fools day joke even though it was five days late already.

"Ben, I hate to break it to you but that's a watch... Look, since I'm up I've got things to do and none of it involves listening to you. Get out Ben." Gwen nodded her head in the direction of the door, this time more sternly.


	2. Chapter 2

(I do not own the rights to Ben Ten Alien Force nor its characters, etc. XD Thanks for the reviews! It inspired me to keep writing what I had planned!)

The words struck Ben harshly and stung him even more intensely than anything else she could have said at that moment. She wanted him out? After he had rushed all the way over to her house to see if she was alright, she wanted him out and didn't want to listen to what he had to say. This just kept getting more and more bizarre. Ben's head spun a little with thoughts as he started toward the door, Gwen close at his heels as though to insure that he did leave. Pausing at the doorway, Ben shook his head slightly and allowed a sigh to escape his lips.

"I'm still confused Gwen but if you want me out, I'll go. Just, please call me if you need me, alright?" he said with honest sincerity, his green eyes examining his cousin's. At those words, she seemed astonished as though she had never expected him to say them. In fact, her guard was completely thrown off by them as though he had broken through somehow. Then suspicion replaced that vulnerability. She still didn't believe him. Did she have no trust in him anymore? Through all the times fighting off alien scum, they had placed each others very lives in one another's hands time and time again and now he was looked at as though he had grown an extra arm. Ben checked himself just incase. Nope, no extra arm.

"What have you done with the real Ben?" Gwen said skeptically though she actually seemed to halfway smile. Her head shook slightly as though she was trying to dismiss a thought but instead she beckoned him back inside the house. "Okay, first you act like you've decided to pull an extremely late April Fools joke which, I might add; you already did on the actual day. Then you act like you're serious about something for once. What's really up, Ben?"

"Hey, I didn't pull a single prank this year! Well… maybe I did hide Kevin's car keys for just a few minutes but that's beside the point," Ben said, the last part causing him to look rather guilty at the end as he shook his head. Quickly he put on a more humorless façade. Gwen didn't seem too convinced by this statement. In fact, her patience was slowly being lost again. He could see it on her face. Since when did Gwen have such a short fuse? Normally she liked to hear him out even if he came to her with some ridiculous things. All of them, of course, true. He hadn't pulled something on her since they were little. Maybe that was it.

"Alright, so, wait, your saying that normally I would come in and make a bunch of jokes at your expense and act really immature?" he questioned getting a positive nod of the head from his cousin. "Okay… Plus, you've never heard of the Omnitrix?" Gwen shook her head this time with an aspirated sigh, her arms folded across her thin body. "What about the Plumbers or aliens?"

"Ben, both of those are things that people have heard of. What do plumbers have to do with this anyway?" Gwen questioned, one eyebrow raised though her tone of voice was much calmer than it had been before. Instead of guarding herself as she had been doing before, she actually relaxed her posture somewhat. Maybe she liked the difference she was seeing within her cousin.

"No, not plumbers like the kind that unclogs toilets. I mean the Plumbers, the group that captures aliens to keep them from hurting people. Alright, I can tell that you don't believe a word of this, Gwen, but just hear me out, okay?" Ben asked of her, hoping that she would comply long enough to get her to understand. He would have to choose his words carefully and pick the right moment to actually show her the physical reality of what he was talking about. He certainly did not want to give his cousin a heart attack if she truly didn't remember.

Deciding that the very best option was to start from the beginning, Ben Tennyson did just that explaining to Gwen about Grandpa Max being a Plumber, him finding the Omnitrix, and them fighting off aliens during their summer when they were ten and how just recently they had begun to fight off the DN Aliens. What he gave her, of course, was the condensed version of everything so that he wasn't kicked out before he could get to the end of his story.

"So, you're an alien," she stated pretty slowly, almost mockingly causing Ben to flinch just slightly. That was a weak spot for him. He wasn't an alien but at the same time it had taken a lot of convincing, mostly on Gwen and Julie's parts, not to think of himself as a complete outcast from the norms of the world. Being able to turn into ten different, or more if he could figure out the code again, aliens was not something anyone besides himself could do, to his knowledge at least. Well, there had been that look alike… Ben quickly snapped himself out of his memories.

"Not… exactly. I can just turn into them. Here, I'll show you," Ben said with a grin as he lifted his left hand and began to turn the dial. Selecting the one he wanted, Ben struck the watch with the palm of his hand and began the transformation. Much as before when he had turned into Jet Ray, his body structure literally changed. This time, however, the bones mostly expanded. Soon, instead of standing as a human boy, Ben was looking down just a tad at Gwen. His body was now green, made up of plant like material, while his head was mostly black incased in red. "Swamp Fire!"

With a cry of disbelief, Gwen stumbled back just a tad, her arms coming up in front of her. Oddly enough, it reminded Ben of the first time she had seen him. The first time that he had seen himself really as one of the aliens when he had first discovered the watch. Only, thankfully, his cousin didn't have a fire extinguisher on her this time. But, knowing his cousin as well as he did, he knew that she would recover quickly. Sure enough, she did only a little hesitantly.

"See?" Ben said in a deeper voice as he gestured with his hands to himself. Then a little smugly this time, "I told you that I was telling the truth." Gwen's green eyes looked him over and she took a tentative step back toward him, her hand momentarily flickering as though to touch him though it went quickly back to her side again.

"Okay, so, you're telling the truth. What now though? I hate to break it to you Ben but as far as I know, none of the things that you talked about happened," Gwen pointed out logically. "I've never even seen an alien before now. Besides, you're like a completely different person than the Ben that I know." The truth was that Ben really didn't know. Not knowing what was going on, of course, didn't help with the decision or plan making much. Then the thought occurred to him and he snapped his fingers together. Accidentally, he created a small spark of fire but it went out quickly.

"We have to find Kevin. He might know what's going on. The only thing is that I got a disconnected signal when I tried calling his phone. That's really odd because he never has it off incase you call him," Ben said with a worried tone to his voice, a hand on his chin thoughtfully. At that, Gwen looked perplexed but she already knew that was another part of the story she didn't remember being a part of. "This is the part where you come up with a brilliant idea to track him." Ben turned to her hopefully.

"Where does he normally hang out?" Gwen questioned with a smile, clearly pleased that she hadn't disappointed him. Ben slapped his own forehead realizing that he could have come up with that if he had actually been thinking. Granted, he did have an excuse the way that the day had been going so far to be a little out of it, but still.

"He's normally in his garage at home working on his car. I would bet that he's still there now. Good thinking Gwen! Let's go," Ben said before transforming back to his human form. "It's not far from here." They would have to walk. Ben didn't want to freak out his cousin anymore than necessary even if she was handling it fairly well so far. Together they both started for the door. Ben moved with determination while Gwen went as though she had entered into a dream world.

"Okay, so, what's this "Kevin" guy like anyway? You keep mentioning him," Gwen pointed out, wondering what the big deal there was with this person. Was he an alien? Clearly he did know, or at least Ben told her that he knew, about aliens and alien tech but Ben had also mentioned the three of them fighting together. Besides using some household items perhaps out of necessity to defend herself with, Gwen personally couldn't see herself fighting off aliens with just her hands either.

"Kevin's really good with alien tech but he can also absorb the energy of whatever he touches. Mostly metals and rocks and things like that now," Ben explained as they walked. He was going far faster down the driveway toward the sidewalk than she was and Gwen had to pick up the pace to keep up with her cousin. Clearly he wanted to know what was going on so that he could fix it and set things back to his form of normality. "Oh, yeah, and you two also went to a school dance together." Gwen stopped in her tracks, stunned for a second by what he was saying. She knew it to not be true, at least to her memory. Then again, how could she doubt what Ben was saying when he clearly believed every word of it?

It was beginning to look like there was only one real answer to this that would explain everything. Neither one of them seemed to be right or wrong. Then maybe they were both right? "Ben, do you remember anything strange happening before you found yourself in your bed?" she questioned and her cousin considered it for a moment before he replied.


	3. Chapter 3

(Once again, I own nothing that has to do with Ben Ten Alien Force. XD Thank you much for reading this!

**Unleash the Shadow:** Oh really? He did remember something, just fragments though. Hm, well, you'll just have to read to find out about Ben from the parallel dimension. Maybe I'll put him in maybe not? Lol.

**Kisdota:** A One Piece fan?! OMG, you rock. XD I could tell by your laugh. =) Well, again, you'll have to read to find out, right? There is a major difference. This is like a big What If? But I'm not saying more… =P)

Ben seemed thoughtful as he considered Gwen's question. Some of his memory was a bit foggy and then completely blank in parts, but he at least remembered the gist of what had happened. Though he was still at a loss as to why everything had turned upside down later. "You, Kevin, and I had just responded to a news story about some strange events just outside of Bellewood at a nearby science lab. Sure enough, there were some DN Aliens there when we arrived. They had some sort of device that they were trying to steal and we stepped in to stop them," he responded, a sort of far off tone to his voice as he recalled it all.

"I turned into Swamp Fire and we started to fight them. Before we could finished them off the last thing I remember was being flung forward by one of them and a blinding flash of light before I woke up this morning." Once he had finished, he turned his head to look at his cousin, wondering what she thought of it. Gwen had always been the smart one, so surely if there was something he was missing she would be able to clue him in about it. Sure enough, that way she had of thinking through things came in handy once more.

"In class we we've just started to discuss the possibility of multiple dimensions besides our own. What you're saying, obviously, is true but at the same time I know it isn't. Maybe that flash of light was what brought you here?" she theorized, one hand gesturing slightly as they walked. "I know it sounds pretty crazy but after what I've seen here today, it's believable and what with alien technology being common where you're from, we shouldn't dismiss the idea."

Gwen had laughed slightly when she had commented how insane her theory, in the context of a normal day in her life, seemed. Though strangely enough, in the end her voice was serious again. This was a dangerous matter if she was actually right. If she was, then what exactly had happened to the Ben she knew? How would they ever be able to switch them again if there was no alien tech to use here? Of course, this was assuming that there were no aliens in her dimension. Could there be? Where there really aliens on Earth? The thought was a little bit overwhelming to her.

"If time travel is possible, that is too," Ben agreed, though he frowned and crossed his arms over his chest. Clearly he wasn't all too thrilled at the idea of having been sent to a dimension, one that seemed fairly parallel to his own, where he clearly didn't have the Omnitrix. To him, that meant that the world was in danger. After all, if there wasn't someone fighting alien scum to keep it safe, then what was there to stop the Highbreed from simply taking it over or destroying it as they saw fit? "It makes the most sense too. Good thinking Gwen."

"Are you actually saying that I'm right and complimenting me?" Gwen asked as though not sure he really wasn't up to something. Mostly it was a reflex. Ben could tell that she still expected him to be a more childish version of himself. With the weight of saving the world on him, Ben Tennyson had grown up when it came to maturity in the last five years. Clearly that hadn't been the case here. Gwen was right. Her theory seemed like the only logical solution now that he thought about it. Ben shrugged his shoulders and laughed a little bit.

"Things are different where I'm from apparently," he pointed out, following it up with a grin. It was strange to think of being from somewhere else other than where he was right now though, since things were so much the same. For a moment, however, he considered the seriousness of the situation. Gwen and Kevin, not to mention his parents, would surely be worried about him. At least all of them knew about his crazy adventures back in his own dimension (he had to keep reminding himself now that the Gwen he was speaking to wasn't the same one he knew) but they would still be looking for him. In response to his statement, Gwen smirked a bit and folded her arms over her blue shirt.

"I honestly like you a whole lot more than the Ben I know," Gwen responded as she shook her head. They continued walking, this time as they elapsed into silence. Thoughts were weighing them down. The consideration of where the Ben was from this dimension if he was here danced through the Omnitrix wielder's mind but without knowing how the device worked that had transported him here, he had no way of knowing that. For all he knew, that Ben could have very well taken his place. It only made sense since he still had the Omnitrix.

Finally they started getting close to where Ben knew Kevin's house to be. He could only really hope that things weren't different as far as where the black haired boy had settled down to live. If so, then Kevin would be able to tell them what the device was that had done this and perhaps how to reverse the process. After all, he had been an arms dealer selling alien tech off to buyers before he had joined up with them to defeat the DN Aliens. At least in Ben's dimension. Ben was having a hard time keeping all of this straight and his head swam a little with the overwhelming considerations.

They neared the house and Ben saw, much to his relief, that it was the same on the outside as he remembered. Thankfulness on his façade, the brown haired boy rushed toward the garage door and began to hammer with one fist upon the metal to draw whoever was inside's attention. Why use the front door when he knew that, parallel dimension or not, there was a ninety five percent, or even higher, chance that Kevin was working on his car inside the garage? Unless things were more backwards than he was aware of, Ben was sure that he would be there.

"Who is it? I'm busy in here!" That was the response that came almost immediately, one that was completely dismissive of them. Ben already had a feeling that he wasn't getting up immediately to come and answer their knock. So he knocked again, louder this time. "Fine, I'm coming!" There was a disgruntled sound from the other side that actually caused Ben to have to suppress his laughter a little bit. He was the same Kevin; immature and completely disrespectful to everyone and everything else but his car. Gwen raised an eyebrow, obviously wondering what was so funny about giving Kevin a hard time. She would just have to wait to find out why.

There was a sound of something clicking together before the metal grinding of the garage door greeted Ben and Gwen's ears. The Omnitrix wielder retreated a few steps and stood waiting patiently till it was all the way up. It didn't take long for a boy to emerge out of the garage. Kevin E. Levin was a bit taller than Ben was himself, a year older, and far more muscular. "If you're trying to sell me something you'd have better luck trying to flap your arms and fly. So I would get flapping." Yes, definitely the same old Kevin. His sarcasm was still intact. His arms were even folded across his chest as usual. He was also wearing his traditional outfit that consisted of a light gray long sleeved shirt under a black short sleeved one, blue jeans, and black shoes. The only thing was that he didn't recognize them at all.

Not that he thought he was supposed to. The only thought running through his mind was that they were annoying distracting him from his mechanics, which was highly annoying.

"You don't remember us?" Ben prodded, trying to see if maybe there had just been a mistake. No, there was no mistaking it when Kevin shook his head and sort of glared in their direction. Only, it seemed like he was glaring more toward Ben. The look seemed to ask, "Am I supposed to?" although no words actually came out of the black haired boy's mouth. With a sigh, the Omnitrix wielder shook his head. Gwen's theory really seemed to be the only answer now. "I'm Ben Tennyson and this is my cousin Gwen. We're not selling anything but we heard that you were." Okay, lying on the spot had begun to be one of Ben's better talents from all of the sneaking around he had done before his parents knew about his turning into aliens to save the world.

Though the obvious lie earned him a scrupulous look from his cousin, Ben simply ignored that and tried to focus on Kevin's reactions. Coming right out and asking if he sold alien technology probably wouldn't have been a good idea. This way, he left the door open for Kevin to tell them more. After a moment of complete and utter silence, Kevin opened his mouth and said, "Yeah, so? You asking to buy or what? You two look a little too young to be Plumbers." With that he raised an eyebrow and looked them both over, though he seemed to pause at Gwen and turn his face away. Was he embarrassed to be seen examining her?

"Bingo," Ben said with a smile causing Kevin to look at him with an odd expression.

"You came all this way to buy a Bingo game?" he questioned with a snicker at the end. Gwen let out a sound of disapproval at that, clearly not amused by his antics, and folded her arms over herself. It hadn't slipped past her, however, that he had mentioned the Plumbers. So there were really aliens that came to her version of the world as well. All this time she had lived next to them and never noticed? The thought was just a little bit disorienting but she felt better almost now that she knew oddly enough.

"Not… exactly," Ben responded slowly, realizing that Kevin had once said that before to him, well, at least something similar when they had gone to rescue his cousin Ken. Personalities in this place seemed to be, except for his, fairly similar to the ones from where Ben was from. That would make this part a whole lot easier. Unless, of course, it really wasn't that easy. If Ben hadn't had the Omnitrix in this world that meant that chances were Kevin had never served time in the Null Void. He could be on the inside, a totally different person. Ben would just have to take that chance and trust him, however.

"We need your help finding out what a certain alien device is; one that transports people from one dimension to another?" Ben asked with a hopeful look. He wasn't sure that it would be one of the many devices that Kevin knew about, after all. "It's sort of complicated but if you could help us out, even a little…"

"Yeah, I know about it," Kevin said, giving a curt nod. "But what exactly is in it for me if I just go blabbing to you what I know?" Ben shrugged his shoulders, at a loss for an exchange idea. He had nothing to offer up that was of any value. Well, at least nothing that he was willing to part with for the information. Instead he turned to look pointedly at Gwen knowing that this was the part where she stepped in and dealt with the black haired boy. It was like she alone had the power to ask him for favors.

"You said we were friends with this guy, why exactly?" Gwen questioned him instead in a whisper.

"It's a bit complicated actually," Ben answered instead to both people's questions, feeling as though he had been pushed in front of the bus having to convince Kevin. "What if I told you that in an alternate dimension we're actually friends who kick alien butt together and save the world on a regular basis?" Kevin began to laugh loudly until he finally regained his ability to speak, once again in a serious voice.

"That's a good one. Seriously, what's in it for me?"

(I know I didn't make Kevin all that evil. At least in this chapter… *hint hint* I'm really leading up to what happens with Grandpa Max. You would think he would be the easiest, wouldn't you? Think again… *hint hint* XD)


End file.
